Sign up or log in to customize your list. Here's how it works: Anybody can ask a question The best answers are voted up and rise to the top I have couple of straight tracks, no curved tracks, so the only option now from me is to buy the new 7499 straight + flexible tracks. How many boxes of 7499 tracks do I need to make a complete oval circuit? There are reviews but none of the is actually mentioning this. Each piece of flex track is equivalent to 1/4 piece of regular track. The standard train curves are 1/16th of a circle and thus an oval shape is not possible, however, with 64 pieces of flex track you could make an oval by squashing the circle a bit. 7499 comes with 16 flexible tracks, so you'll need 4 of them to make a regular train circle. The flex track can be used to make a smaller circle than the regular track: but as TheBrickBlogger pointed out, the flex track has performance issues and such a tight circle will be difficult for your trains to navigate.
The trains tend to fall off if conditions are not perfect. Over Christmas I built a large layout under my Christmas tree and I had to remove all the flex track in order to prevent derailing. Part of that was due to my train design, part of it was due to the fact that the track was sitting on a mix of carpet and hardwood flooring, but part of it was that the train is very sensitive to bumps in the track and flex track exacerbated those issues. Depending on your engine design you might have more or fewer issues. If you are just pushing the train by hand, it will probably be fine. Also keep in mind that the standard lego train car with fixed (not swiveling) wheels can only navigate a certain minimum radius. Lego puts the wheels 10 studs apart so that they can just barely make it around the fixed curves. If you build the small flex circle, or squash a 64-flex-track circle into an oval, your tightest curves will for sure be too tight for those cars to navigate. Normally Lego sells curved track in an expansion kit.
It seems that right now (May 2015) the only kit is the 7895 Switching track kit. That kit comes with 4 curved rails and so you'd need to buy 4 of them to make a circle. If that's not your ideal choice of parts, then Bricklink would be best. Or, use this as an excuse to buy a whole train kit, which comes with track, train cars, motors, etc. You can never have too much Lego. The flexible tracks are not designed to make a full oval, but to add subtle, smaller curves in a train layout, using just a few at a time. If you do use too many flexible tracks next to each other they will slow down your train, they are very noisy, and can even derail the train. Here is an excellent comparison video between the regular curved tracks and the flexible tracks: http://youtu.be/fGcD_QtOcRQ If you would like to create a full oval I would suggest that you just get the curved train-tracks on BrickLink as they are currently not available directly from LEGO (except in full train sets). They are about 50 cents each and will be much better for your purpose.
To add to the excellent answers already provided, the cheapest LEGO train set currently available giving you a full oval/circle is 60051 and costs $149.99 in the US Lego store. ( (currently $149.99 so same as LEGO store) sometimes. The equivalent purchase of 4x 7895 Switching Track is $15.99 in the US Lego Store for each set, so a total of $63.96 for 4. If you go by absolute price, the 4x7895 is your best option, and you get 8 switches extra, which you could use once you expand your track, or sell back through bricklink or eBay (current US selling price on bricklink is around $3 per switch track) which would reduce the total price by $24, giving you a total price of roughly $40 for the oval. The 60051 train set does come with batterybox, trainmotor, IR set etc, plus many pieces. The value of that set is probably better than 7895 gives, at a roughly $100 premium over 4x7895 with sellback via Bricklink/eBay etc. Separately, there are 2 more options you can consider:
ME Models sells LEGO curve sets with bigger radius than the standard R40 LEGO curves. Their R56 curve pack costs $19 for a half-circle (so $38 for a full circle) plus shipping. They have several other radia as well, but those will cost more. From what I've read the fit with "normal" LEGO is very good and train enthusiasts love these rails. If you don't mind the extra pieces, you can make curves out of straight rails by using this technique (youtube) . The train's movement will be a little jerky but otherwise it works well. You'll just need a lot of space as the radius of such an oval is very large. But most LUGs use this technique in their train layouts, so it is "endorsed by professionals". Basically, you offset the outside joint by half a stud every rail using a 1x3 and a 1x2 jumper. The upside is that you can use this technique to make the outside of the curve 1 plate higher than the inside of the curve to allow your train to "bend" through the curve just like trains in real-life do.
Sign up or log in Sign up using Google Sign up using Email and Password Post as a guest By posting your answer, you agree to the privacy policy and terms of service. Not the answer you're looking for? Browse other questions tagged trains or ask your own question.Here are some more advanced ideas for LEGO train layouts, while still keeping consistent with the restrictions of track geometry. While none of these ideas are original to myself (with the possible exception of the yard at the bottom), I hope this explanation will inform and inspire you to build better and hassle-free LEGO layouts. New as of Jan 7 2008: this page is now available in Italian courtesy of ITLUG, the Italian LEGO® Users Group. You can see the Italian translation on the ITLUG Web site. (EDIT 9/15/2008: updated URL) Note: This page was originally written several years before LEGO switched from powered 9V track to all-plastic track with battery trains. If you are using the all-plastic track you can ignore considerations of short circuits (see the Wye oh Wye? section).
Also, the Flex Track piece is not included in this discussion; that makes some track shapes easier to achieve, though trains are more likely to derail on Flex Track than normal track that is assembled according to the principles on this page. The all-plastic Double Crossover track is also not included. LEGO track geometry is very limiting. There are only a handful of available pieces. From left to right, these are: straight, curve, left switch (or point), right switch, and cross track (There is also the newer Flex Track piece, but it is not covered by this document): Each straight track piece is 16 studs long and 8 wide. The curved pieces produce a 22½° bend, so that 4 of them make a 90° turn. The switches have a different kind of curve in them, and they are meant to be used in conjunction with a curved track to produce parallel tracks. Here are some of the basic track concepts that are valid with LEGO track. Each one preserves perfect alignment with the studs on the large grey baseplate (48×48 studs).
Straight track can go anywhere. But in order for the alignment of tracks to be maintained consistently through curves and switches, it is necessary to adopt some standards. The standard that works best is: If you follow these rules, you will never have trouble getting your layout to line up. On first glance you may think this is too limiting, because the following restrictions would seem to be implied by the above rules: However, there are some additional things you can do with LEGO track geometry that do not violate our rules. This is because in the real world, there is a little bit of slack in the connections, and the studs can still be made to line up with certain alternate configurations. A crossover is where you have two parallel tracks with a line connecting them. The standard way is to take the switch geometry described above, and create a crossover where the two switches line up with a pair of curved tracks in between. But look at the right hand crossover: it also lines up, only instead of the two curves there is a single straight piece:
How does this work? Well, it turns out that 2 curved track pieces, when positioned at 22½° from horizontal, have the same amount of vertical distance between start and end as a single straight at that angle. Also, the horizontal distance is almost exactly double that of a straight. But what if you put nothing in between? Then the tracks don’t line up right:The areas circled in red are not lined up properly. If you want these tracks to line up elsewhere on your layout you will run into problems. Just add a straight or two curves (or two curves and several straights, to make a parallel track in between). Remember, a switch is NOT the same as a curve! It’s not just crossovers that let you replace two curves with a straight. Here are some other situations where this trick can help avoid unnecessary zigzagging of your trains. A standard "S" curve (left) is made with eight curves. But replace the two middle curves with a straight (right) for a smoother shape that uses less space.
A branch line coming off a switch can be given a gentler curve, and take up less real estate, with the same technique. You can loop back on yourself by replacing 2 curves with a straight. A crossover requires extra space between the parallel tracks. Here’s one way, using both types of "S" curves, to separate them enough for a crossover without interfering with spacing on the rest of the main line. A wye (named for the letter Y) is one of the most common ways for trains to turn around, and it allows you to connect the loops of your layout in different ways for interesting variations. Caution: a wye made of powered LEGO (or any DC model train) track will have a short circuit! You will need to electrically isolate the track segments in at least one spot in order to make it work. You can do this by inserting paper between the track pieces before connecting them, and then cutting away the excess. Of course, if you are using plastic track that consideration does not apply.
The wye on the left uses standard LEGO geometry, with 4 curved tracks in each 90° turn. In the one on the right, the double curves (3 sets of them) are replaced by straights. This shrinks the size and produces more reasonable curves. Another convenient coincidence that comes in handy when designing layouts involves a straight track running at a 22½° angle. If you use 12 straight tracks with a curve at either end, you can still line up your track at both ends while having a more unusual track angle. This works because of the magic of Pythagorean triples. Like the well-known 3-4-5 triangle, you can make a perfect right triangle using dimensions of 5, 12, and 13. In such a case, the angle is 22.62°, which is close enough to 22½ that it works. Thanks to Jason Railton for pointing this out. But why is it 12, and not 13, you ask? Remember above where you can replace 2 curves with a straight? The 13th straight is replaced by the curves at either end of the 12. Note that a horizontal track of 12 units will line up nicely with the end of the diagonal track.
This trick only works if the begin and end of the turn are parallel. If you want to have the begin and end be perpendicular, you need an extra straight. There are no Pythagorean triples that produce anything close enough to a 45° angle, but we can use math to derive a result anyway. Trigonometry tells us that the distance traveled horizontally or vertically for each unit of diagonal movement is the sine of 45° (or cosine if you prefer; they’re equal for a 45° angle), or 0.7071. This is also half of the square root of 2 (1.4142). So we need a number that, when multiplied by 0.7071, produces something close enough to an integer that it will work with LEGO track. 1 x 0.7071 = 2 x 0.7071 = 3 x 0.7071 = 4 x 0.7071 = 5 x 0.7071 = 6 x 0.7071 = 7 x 0.7071 = 8 x 0.7071 = 9 x 0.7071 = 10 x 0.7071 = 11 x 0.7071 = 12 x 0.7071 = 13 x 0.7071 = 14 x 0.7071 = 15 x 0.7071 = 16 x 0.7071 = 17 x 0.7071 = 18 x 0.7071 =
19 x 0.7071 = 20 x 0.7071 = The best choice is 17 straights, but you should be able make 10 work also. Thanks to Larry Pieniazek, David Koudys, and Jeff Van Winden for their postings in a thread about this topic on LUGNET. Note: this requires that the beginning and end be perpendicular to line up properly. If you need the beginning and end to be parallel, add a right angle turn (four curves) to the above. You can simplify it by replacing two of the curves with a straight, but you will still need to go the “wrong way” with one curve track in order for it to line up: You can add a switch and curve to each end, or replace the two resulting curves with a straight, just like we did in the earlier crossover: The result is a pair of switches separated by 14 straights. Put several of these together, and you have a switching yard: We can also do the same thing with a 45° track: Here is a big switching yard that uses several of the ideas shown here: